The panel called for a high-level meeting at the UN General Assembly and independent health threats council led by heads of state to galvanize action.
Russia has denied previous accusations by Ukraine and Western nations of possible war crimes and has also denied targeting civilians in the war.
Health authorities are investigating the origin of 169 reported cases of inflammation of the liver in children in 12 countries.
"Given the uncertainties of the current situation, there are no assurances that the war will not get worse," WHO's European head Hans Kluge said.
The Sputnik V shot, widely used in Russia and approved in more than 60 countries, is also being reviewed by the European Medicines Agency (EMA).
Following the first case of child polio in 30 years, the number of children vaccinated against polio in Jerusalem increases almost fourfold.
In January, COVAX, the global vaccine program run by Gavi and the World Health Organization (WHO), had 436 million vaccines to allocate, but low-income nations only asked for 100 million.
Dr. Dorit Nitzan explains the difference between Omicron and the new sub-variant, and why there may be bigger issues at hand.
The Pfizer vaccine against COVID-19 was the first to see proper usage in the pandemic and remains a reliable vaccine of choice in many parts of the world, including Israel.
Two separate outbreaks of bird flu in a town in northern Israel led the Agriculture Ministry to announce a state of emergency on Saturday night.